Question

Which of the following statements is /are correct?

• A. Hydrolysis of $NaHC{O}_3$ salt is cationic hydrolysis and the solution is acidic
• B. Hydrolysis of $CuS{O}_4$ salt is cationic hydrolysis and the solution is acidic
• C. Hydrolysis of $NaCN$ salt is anionic hydrolysis and the solution is alkaline
• D. Hydrolysis of $NaHC{O}_3$ salt is anionic hydrolysis and the solution is alkaline

Answer 1

Answer: (B), (C), (D)

The correct options are
B Hydrolysis of $CuS{O}_4$ salt is cationic hydrolysis and the solution is acidic
C Hydrolysis of $NaCN$ salt is anionic hydrolysis and the solution is alkaline
D Hydrolysis of $NaHC{O}_3$ salt is anionic hydrolysis and the solution is alkaline

$1.$Cationic hydrolysis refers to the cation of a salt hydrolyzing. This salt would be the result of a reaction between a weak base and a strong acid and the solution would be acidic in nature.

Assume a salt $BA$ where $B^{+}$ is cationic part of a weak base and $A^{-}$ anionic part of strong acid.
$BA+H_{2}O⟶BOH+A^{-}+H^{+}$

$2.$Anionic hydrolysis refers to the hydrolysis of the anion of a salt that is fromed due to the reaction of a strong base and weak acid and the solution is alkaline in nature.

Assume a salt $BA$ where $B^{+}$ is cationic part of a strong base and $A^{-}$ anionic part of weak acid.

$BA+H_{2}O⟶AH+B^{+}+O{H}^{-}$

$NaHC{O}_3$: salt of a strong base $\left(NaOH\right)$ and a weak acid $(H_{2}C{O}_3$ so anionic hydrolysis takes place and the solution is alkaline.
$CuS{O}_4$: salt of a weak base $\left(Cu\right(OH{)}_2)$ and a strong acid $H_{2}S{O}_4$ cationic hydrolysis takes place and the solution is acidic.
$NaCN$: salt of a strong base $NaOH$ and a weak acid $\left(HCN\right)$ anionic hydrolysis takes place and the solution is alkaline.